Terminal for electric power cable systems



Dec. 5, 1950 c. E. BENNETT TERMINAL FOR ELECTRIC POWER CABLE SYSTEMS 2 Sheets-Shea t 1 Filed Dec. 15, 1945 W I l v6 2 g INVENTOR.

2 Sheets-Sheet 2 Filed Dec.

JNVENTOR.

ATTOQ/x/EY i 'atented Dec. 5, 1950 TERDHNAL FOR ELECTRIC POWER CABLE SYSTEMS Charles E. Bennett, Ridgewood, N. J assignor to The Okonite-Callender Cable Company, Incorporated, Paterson, N. 3., a corporation of New Jersey Application December 15, 1945, Serial No. 635,344

1 Claim. 1

My invention relates to an improvement in terminals or potheads for electric power cable systems and has for one of its objects to provide a terminal which is of new and novel construction as compared with existing devices.

When installing electric power cable systems it is customary to provide the terminals required for the job and at least one spare. A typical installation requires six terminals and at least one spare. An average cost to the customer is around $700 per terminal, a total cost in this instance of $4900 for terminals alone.

The present invention provides a construction wherein a saving in costs to the customer is effected, in that instead of carrying a spare terminal it is only necessary to carry a spare bushing, the cost of which would only be $239. Not only is a savin effected in costs, but in time as well inasmuch as the conventional terminal bushing is for the most part of special design and it often takes from ix to eight months to build them.

Another advantage in my construction is the ease of assembly, my invention providing a terminal the only cemented parts of which are a ring cemented to the upper and lower ends of the terminal bushing. All other fittings are simply bolted together so that the only tool required for assembling is a wrench. I might mention also that in terminals for electric power cable systems the bushing is usually the only part destroyed on failure of the terminal, and my terminal is equipped with a bushing of such construction as to enable the customer economically to carry the same as spares, and to replace a defective or injured bushing with a new one with the minimum of efiort and in minimum time. With conventional terminals it is necessary to carry a complete terminal as a spare which is much more expensive in money invested and in time required to remove the defective terminal and install a new one.

In the accompanying drawing Fig. 1 is a part sectional elevational view of a terminal embodying my invention;

Fig. 2 is an elevational view of the insulator or bushing of the terminal illustrated in Fig. 1;

Figs. 3 and 4 are enlarged sectional views of the flange structure at each end of the insulating bushing of Fig. 1.

Referring to the drawing in detail 2 designates the insulator or bushing of my improved terminal. Thi insulator or bushing which is of novel construction is made up of a porcelain tube provided adjacent each end with a metal cou- 2 pling or mounting ring 6, rigidly and permanently secured to the insulator by cement 6, or other suitable means providing a liquid-tight permanent seal between the rings and the insulator.

ii designates the pipe or riser of an electric cable system upon which the terminal is to be mounted. This riser is coupled to a metal cone it by sealing coupling l2.

The lower end of the bushing or insulator 2 is inserted into the upper end of the cone l0. T is cone is provided with a peripheral flange l3 and bolted to the flange a gasket compressing ring It for compressing sealing gasket it. The end of the bushing 2 is received by the sealing gasket as will appear from the drawing so by setting up the bolts it which pass through the flange i3 and ring i i a hermetic seal is provided between the bushing 2 and cone IS. The bushing is coupled t cone by flange E3 of the cone, the ring l ich as above noted is permanently aimed to the bushing and the bolts i'i. By simply loosening the bolts l5 and removing the bolts ii the lower end of the bushing is free to be removed from the cone Ill.

The terminal bushing is kept filled with oil or other suitable insulating rluid, which in some types of power cable systems may be under pressures as high as 200 to 225 pounds per square inch. In this regard it is to be noted that the cement bond 6 between the ring and the bushing 2 is maintained out oi contact with the pressure fluid by the sealing gasket so that the bond will not deteriorate due to contact with the pressure fluid.

The cable to be ter mated it will be understood passes up th the bushing 2 to the upper end thereof where it is attached to connector i8 by which the cable is connected to the line. This is conven ional practice.

28 designates a cap piece or cap ring which rests upon the top of the bushing 2, this memher being provided with peri heral flange 2|. Below the top of the lat. hing I provide a gasket compressing ring 22 for compressing the sealing gasket 24 which surrounds the bushing above the bushing ring i, the desired compression of the gasket being obtained by setting up the bolts 25 which pass through the ring 22 and flange 2!. This provides a hermetic seal for the upper end of the bushing 2 and inasmuch as the gasket lies above the union of the ring to the bushing the cement 5 is always maintained out of contact with the pressure fluid in the bushing and deterioration prevented. To complete the mounting of the bushing the ring t and flange 2| of the cap ring are coupled together by bolts 26.

It will be apparent from the foregoing that the cement 6 by which the rings 4 are attached to the upper and lower ends of the bushing 2 is sealed off out of contact with the oil or other pressure fluid within the bushing.-

As above explained it is customary with prior terminals to replace the entire terminal. This is by reason of the construction employed and involves an expense of as much as $700 for the terminal alone to which must be added the time required for disconnecting and removing one terminal and substituting another. My construe tion very materially reduces this expense in that in my case it is necessary merely to remove the bushing 2 and replace it with a new one, which is a relatively simple matter necessitatin only loosening of the bolts l5 and 25, and removal of the coupling bolts I l and 26. The bushing 2 'may then be removed, a new one substituted and the bolts tightened up again. Because the rings 4 are originally permanently secured to the bushing no time is lost waiting for the cement 6 to set up when installing a new bushing, and no tools other than a wrench are necessary to make the installation.

What I claim is:

A terminal for terminating electric power cable systems, said terminal comprising, in combination, a fluid-filled insulator for the reception of the conductor to be terminated, a flanged cap piece resting upon the top of the insulator; a mounting ring encircling and permanently sealed to the insulator adjacent each end of the insulator; a sealing gasket and a compression ring therefor encircling the insulator adjacent its lower end; a sealing gasket and a compression ring therefor encircling the upper end of the insulator below the mounting ring and cap piece at this end of the insulator; bolts passing through the flange of the cap piece and the adjacent compression ring for compressing said gasket; bolts passing through the cap piece flange and bushing mounting ring for securing the cap piece in place; a hollow member at the lower end of the insulator through which the cable conductor extends to the top of the interior of the insulator; a flange encircling the said hollow member at its upper end; a sealing gasket and a compression ring therefor encircling the insulator between the adjacent insulator mounting ring and the lower end of the insulator; bolts passing through the last-mentioned compression ring and the adjacent insulator mounting for compressing said gasket; and bolts passing through the flange of the hollow member and the adjacent insulator mounting ring for attaching the insulator to the hollow member.

CHARLES E. BENNETT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,182,146 Crispin May 9, 1916 1,304,469 Frank 1 May 20, 1919 1,807,880 Skvortzofi June 2, 1931 2,099,666 Terpak Nov.- 16, 1937 2,116,419 Wetherill May 3, 1938 2,354,191 Bennett July 25, 1944 

